Anton From Perm

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Posts Tagged ‘Python

How to make a Russian regional thematic map

with 5 comments

Nathan at Flowing Data explained how to create a US County thematic map using free tools and it immensely helped me doing the same for Russian regions.

The Result

Inward FDI Performance Index 2005-2007

Step 1: Get the blank map

Unfortunately, we can’t take the blank Russia SVG map from Wikimedia Commons. First, it doesn’t take into account the latest mergers in 2008 (Irkutsk Oblast + Ust-Orda Buryat Autonomnous Okrug = Irkutsk Oblast, Chita Oblast + Agin-Buryat Autonomous Okrug = Zabaykalsky Krai). Second, the regions aren’t identified in the SVG file by their ISO_3166-2:RU code, but by their concatenated transliterated names. Third, the Federal Service of State Statistics doesn’t publish figures of several regions (like Yamalo-Nenets Autonomnous Okrug) because they fall under the administrative jurisdiction of other federal subjects of Russia (in this case Tyumen Oblast). It means that we have to group these regions together so that they can “inherit” the data visualization from their respective jurisdiction.

Get the new map I just uploaded to Wikimedia Commons here.

Step 2: Run python script

You can simply follow Nathan’s blog post and write it yourself, or use mine instead. I wrote it because I am too lazy to rewrite the script each time I want to colorize a map with different parameters.

Get it here (don’t forget to get BeautifulSoup first),: http://pastie.textmate.org/713719

Sample usage: python chloropleth.py -d Inward_FDI_Performance_Index_2005_2007.csv -c RdYlBu6.dat -l IFPI.dat -i Russia2009blank.svg -o IFPI.svg

Parameters

  • -d : Region specific data. Remove the headers and save it as a CSV file. Put the ISO3166-2:RU code into the first column, and the value into the second column
  • -c: Color scheme. It’s a simple text file containing the hexadecimal colors in reverse order, e.g. #D73027 #FC8D59 #FEE090 #E0F3F8 #91BFDB #4575B4
    Use ColorBrewer to help you select the colors to use.
  • -l: Legend file, e.g. 1 0.5 0.25 0.10 0 -0.1 The script will assign the last color in your list if the data point is above the first value in your legend file, and so on
  • -i: Input SVG file, i.e. the blank map
  • -o: Output SVG file

Enjoy

Written by antonfromperm

November 25, 2009 at 12:02 am

Easily unpivot data using Python

with one comment

Denormalized data in multiple columns

I was looking for an easy way to unpivot data, i.e. expand values from multiple columns in a single record into multiple records with the same values in a single column.

Normalized data in multiple records

Since the only tool available was SQL Server/SSIS, I wrote a short script in python (less than 50 lines of code) to easily unpivot CSV data.

Get the code here: http://pastie.textmate.org/713615

Options:

  • -v Verbose
  • -i Input file
  • -o Output file
  • -c Number of columns to be “frozen”, the default is one

Sample usage:
python unpivot.py -v -i GRP.csv -o GRPunpivot.csv -c 1

Written by antonfromperm

November 23, 2009 at 11:16 pm